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-rw-r--r--demo3/repeating_signal.py46
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diff --git a/demo3/repeating_signal.py b/demo3/repeating_signal.py
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+# Python modules
+import time
+import signal
+
+# 3rd party modules
+import posix_ipc
+
+# Utils for this demo
+import utils
+
+
+MY_SIGNAL = signal.SIGUSR1
+
+
+def handle_signal(signal_number, stack_frame):
+ message, priority = mq.receive()
+
+ print ("Ding! Message with priority %d received: %s" % (priority, message))
+
+ # Re-register for notifications
+ mq.request_notification(MY_SIGNAL)
+
+
+# Create the message queue.
+mq = posix_ipc.MessageQueue(utils.QUEUE_NAME, posix_ipc.O_CREX)
+
+# Request notifications
+mq.request_notification(MY_SIGNAL)
+
+# Register my signal handler
+signal.signal(MY_SIGNAL, handle_signal)
+
+# Get user input and send it to the queue.
+msg = "42"
+while msg:
+ print ("\nEnter a message. A blank message will end the demo:")
+ msg = utils.get_input()
+ if msg:
+ mq.send(msg)
+
+print ("Destroying the message queue.")
+mq.close()
+# I could call simply mq.unlink() here but in order to demonstrate
+# unlinking at the module level I'll do it that way.
+posix_ipc.unlink_message_queue(utils.QUEUE_NAME)
+